Friday, August 1, 2014

yeast14, August 1, Friday

=> Vacuole pH in replicative aging, Gotschling lab.
Vacuole acidity is reduced during aging and is asymmetric. Hughes Nature 2012

plasma membrane H+-ATPase has the opposite asymmetric pattern from vacuole acitiy between mother and daughter cells.

Pma1

Quinaccine, vacuole acidity
Vph1-mCherry

1 million of Pma1 on plasma membrane, 100K ATPase on vacuole. only 3000 free protons in cytoplasma ??

Glucose activate Pma1(ATPase), so low glucose decrease ATPase activity.

Proton diffuses very fast, so cytoplamic proton are instaneous. Yet, proton gradient are observed.

Tor1 activity affects vacuole activity.

=> Peroxisome
major ROS producers, similar to liver bile function. peroxisomes always split, but do not fuse.

older peroxisome have different membrane compositions
older peroxisomes are retained in older mother cells.

Older peroxidsomes are removed by autophagy.

Peroxidsome division is similar to mitochondria divisions. Drp1

=> translocation of cyclin C (cnc1) to mitochondrai mediate stress induced fission and programmed cell death
Randy Strich
Chen JCB 2003, AY JCS 2010, mitochondrial fission and fusion

Good: fusion, Bad: fission
H2O2 induce mitrochondria fission

Drp1 control mitochondrial fission

cyclinC does not cycle and do not control cell cyle. Instead, regulate trancription of stress genes.














No comments:

Post a Comment